- Financing entity
- Ministerio de Economía, Industria y Competitividad (MINEICO)
- Duration
- 2017-2020 (3 Años)
- Principal investigator(s)
- Dr. Paula María Carmona Quiroga
- Budget
- 142.000,00 €
- Official web
1/3 of the Spanish soils contain sulphates that require for construction the use of sulphate-resistant (SR) cements processed from clinker with a low C3A content (from 0 to 5 wt.% in OPC), but these solutions are not always satisfactory because they just prevent expansive ettringite precipitation, but they do not curb gypsum or thaumasite precipitation. Thaumasite is an expansive salt in spite of its low formation puts cement structures such as foundations, tunnels, dams, bridges at risk. None of the current commercial SR cements would resist a thaumasite form of sulphate attack. Very recent studies (from the last 3 years) have shown the potential of Ba ions (added to cement as BaCO3 additions) to immobilise sulphates from the medium by precipitating a highly stable and insoluble salt, barite (BaSO4) and inhibiting not only the precipitation of ettringite, like conventional SR cements, but also thaumasite as a preliminary thermodynamic study has also revealed. However, the current knowledge is still limited, and more research is needed in order to develop new and improved SR cements with BaCO3 additions.
The main aim of the proposed work is to establish the potential of this novel cement system. This aim will be achieved by combining experimental techniques with geochemical modelling to strengthen the experimental evidence by offering a long-term perspective.